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EXHIBIT G Water Information General Mining at the Duckworth Pit will intercept shallow groundwater, which lies from 3 to 6 feet below the current ground level. Deeper bedrock aquifers that underlie the site will be unaffected by the mining operation because of the shallow depth of excavations. Upon completion of mining, two ponds will remain unsealed for recreational and wildlife purposes. The resulting ponds will cover an area of approximately 37 acres. Local surface water ponds, ditches, water courses, and tributaries are shown on the pre- mining map. The nearest water course is Idaho Creek. No impact to Idaho Creek is expected as a result of mining. Potential Water Resource Impacts The Duckworth Pit sand and gravel operation will have minimal impacts on the water resources in the area. The nearest domestic wells are part of the St. Vrain and Left-Hand water service area. Similar wells in the area are in closer proximity to other existing sand and gravel mining activities and are therefore not likely to be impacted by Duckworth operations. A portion of the Smith and Emmons ditch will be relocated to facilitate mining. After sand and gravel excavation, compacted overburden and/or sandy siltstone bedrock will placed along pit walls to minimize impacts to nearby water resources. Discharge Permits The proposed mine will be dewatered and operated as a dry mine. Alluvial groundwater from pit dewatering will be discharged into Lighthouse Cove and Idaho Creek. The applicant has a Colorado/NPDES discharge permit for the pit and will discharge in accordance with permit conditions. Surface Water Management A surface water management plan is in effect for the currently permitted operations; this plan will be updated to incorporate the Duckworth Pit. Consumptive Water Ilse The anticipated consumptive uses For water associated with the proposed amendment can be described in a Substitute Supply Plan (SSP). Duckworth Pit DMC Ill Permit Page !4 of 45